Bill O’Reilly, Soledad O’Brien, and Bill Maher’s Irish roots were uncovered in this week’s episode of Finding Your Roots, Jr. on PBS, and it turns out, O’Reilly and Maher are related. O’Brien is also related to another of the show’s previous guests – Stephen Colbert.

The episode, “The Irish Factor,” used a combination of archival research and DNA testing to explore the commentators’ shared Irish heritage, despite their disparate backgrounds and varied political beliefs.

But the big reveal on the show was when researchers told O’Reilly that he was related to another famed talking head. The show’s host, Harvard professor Henry Louis Gates, Jr. instructed O’Reilly to turn the page in the genealogy book the shows researchers assembled for him, and when he did it revealed a photo of Maher.

The two are distant cousins, related through a common male ancestor from the Kingdom of Breifne, which existed between the 13th and 17th centuries on the Connaught / Ulster border.

“Oh, geez,” O’Reilly joked. “You’re going to have to put him on 24-hour medical watch. This ruins his career. This destroys him.”

“It just shows you what a great place America is. Because we’re about as opposite as you can possibly get,” he said.

The same test was used to determine that O’Brien was related to Colbert, who share an identical strain of DNA, making them distant cousins.

The discoveries were made by CeCe Moore, the show’s DNA analyst, who tested O’Reilly and Maher’s Y chromosomes, which are passed through male family lines, and found a common ancestor. Another test of autosomal DNA, which can trace both male and female ancestors, also showed that the two share a second common ancestor from about 500 years ago.

“We’re all connected if you go back far enough,” Moore said. “These two are a little bit more recent than most of us.”

Maher, it turns out, is also related to Gates, Jr., the show’s host, whose great-great-grandfather was Irish. Both are descendant from Niall of the Nine Hostages.

The show also looked at the paternal side of CNN news anchor Soledad O’Brien, whose father was an Australian Irish man and whose mother has Afro-Cuban roots.

Growing up mixed-race in a predominantly white town on Long Island, she said, was difficult.

“You would have these moments where it would suddenly become very clear to you that you really didn’t belong here,” she said.

She was always interested in her roots, but O’Brien was mostly cut off from her Irish heritage, because when her father emigrated from Australia, he left the stories of Irish immigration behind.

“I think my dad very intentionally did not want us to harken back to our roots. It was just like, you are Americans now and this is the life we’re helping you build, and it’s a different life. So who you’re relatives are is interesting, but you don’t need it to move forward,” she said.

Throughout the episode, facts about O’Reilly’s, Maher’s, and O’Brien’s ancestors are revealed through careful research and long hours behind the scenes – all of which was new to the subjects. Among the revelations included the fact that O’Reilly’s grandfather fought at the Battle of Argonne in World War I; Maher’s grandfather during the same time was leading a strike of the New York boatsman union for an 8-hour day and fair wages; and O’Brien was not in fact related to Brian Boru, despite family lore.

For more on the three reporters’ family history, the whole episode is currently available here, on PBS.org.